Derivatives of propionic acid have been employed in reactions with mercaptans to provide alkyl or aryl mercaptopropionic acids. Usually the acrylic ester or nitrile is employed in a reaction with the mercaptan to provide a thioether. In a few experiments the thioether has been oxidized to the sulfonyl derivative. A publication by C. D. Hurd and L. L. Gershbein in J.A.C.S. 69, 2328-2335 (1947) provides a typical example of such reactions.
Polycarboxylates have been employed in the salt form with a mercaptan to provide an alkyl thioether substituted polycarboxylate. The reaction is reported to provide solid derivatives which are acids and can be titrated to confirm their identity. For example, appropriate mercaptans are reacted with disodium maleate which provide solid derivatives of alkyl mercaptans. Various S-alkylmercaptosuccinic acids are reportedly prepared by J. G. Hendrickson and L. F. Hatch in J.O.C. 25, 1747-1752 (1960). Very low yields of the substituted polycarboxylate are reported.
Also, mercaptans or thiols have been reacted with acrylyl chloride to provide compounds such as 3-ethylthiopropionyl chloride. The acids are also reported to be prepared and 3-t-octylthiopropionic acid has been prepared by the reaction of t-octanethiol with acrylic acid in a basic reaction medium containing triethylamine. A relatively good yield of high purity acid was obtained. This is reported in J. Org. chem. 29 (7), 1910-1915 (1964) by A. A. Schleppnik and F. B. Zienty.
Thioethers have been known to be oxidized to the sulfone with an oxidizing agent. For large scale production it was suggested that chlorination in aqueous solution be employed to convert thioether to the sulfone. Oxidation of the crude thioether reaction product dissolved in water by means of chlorine oxidation has also been disclosed. One such example is found in Acetylene and Carbonmonoxide Chemistry, pp. 156 and 157.
There has recently been discovered novel sulfone mono-peroxy and diperoxy acids exhibiting extra ordinary stability and attractive properties for use as bleach for laundry detergent use. Examples of such sulfone peroxy acids are found in U.S. Pat. No. 4,758,369 and U.S. Pat. No. 4,824,591. The sulfone peroxy acids have exhibited unusually favorable properties as bleaches for detergent use in home laundry detergents. Production in large volume to supply such need has not been heretofore available. There is thus needed a convenient, efficient and safe process for preparing sulfonyl acids, the precursors for sulfone peroxy acids.